Protecting device for bleed passages



'H. G. CARLSON PROTECTING DEVICE FOR BLEED PASSAGES June 3', 1930.

Filed Oct. 51, 1927 Patented June 3, 1930 I A S 1 e mromczi HJALMAR a.crimson, or woncnsrs'a, MASSACHUSETTS, ASSiGNOR 'ro'nookwoon j SPRINKLERCOMPANYVOZF,MASSACHUSETTS, on wononsrnn, -1vrAssAoHUs rTs, "A

' LCQBPORATIQNV onMAssAo UsEr'rs V rnorric'rme nEvIqE' FOR stnnnrassaen's Application filed 'flctob'er; 31(1 '2'7. Serial in, 229,988.

This invention relates ,to means for pro tecting a bleed .passageparticularly adapted for use in a dry-pipe sprinkler system. 7

vIn freezing weather air under pressure is 5 maintained in the sprinklersystem, its pressure automatically, holding. its dry-pipe valve shut, Ifheat meltso en one of the sprinklers, the'suddenreleaslng of this aircauses thesystem pressure to go down sudchamber of the exhauster causesit to open its valve, thereby discharging the compressed. air from thesystem and hence shortwater to the fire. Tosaveair pumping during thewarm weather it is more or less the custom to set the dry-pipe valveopen and fine silt-that merely testing the, system by opening it whenset dry may plug the filter and render the device useless.

.The principal object of myinvention is to provide a simple automaticmeans'for protecting the bleed passages in devices operatingin thismanner from being obstructed 3 by the deposition therein, or in thepassages leading thereto, of substances such as 'dirt I i designed toprotect itfroms'olid particles or silt.

Other objects and advantages of the invention will appear hereinafter.

Reference is to be had to the accompanying drawings in' which Fig. l isa central sectional View of an air Y exhauster for use with a dry-pipevalve for a sprinkler system illustrating a preferred embodiment of thisinvention, and

Fig; 2 is a central sectional view of the protector for thebleedopeningg on enlarged scale. V

I have illustrated the invention as applied to a type of air exhaustersuch as that set forth in prior Patento. l,504,811, patdenly when thebottled up air in the lower ening the period of time. required to get IThis is shown as a simple self-contained ele-' 'ment adapted to beplaced on the head o'fthe entedAugust"l2, 1924 and in thepatent [toGeorge I. Rockwood, No. 1,502,879, patented Ju1y.29,1924; a w

' Asset forth in the said patents the invention is" shown as appliedto asprinkler sys tem having an a r ,exhauster comprlsing a casing 15 in twoparts, as shown, provided. 'withhan exhaustchamber 16 and an airstoragechamber 17.. The chamber'16 will 30 be understood to be 7connected with the sprinkler: system as in said patents and thischamber'also has an exhaust passage 19' adapted to be closed by a valve20mountcd on a pivoted lever 21'and adjustable in any usual way thereon.This frame ispivoted on a stud 22 in the casing and chamber 16.

As described in said patents the chambers 16 and 17 are separated by adiaphragm-23 on which is mounted a valve lifter 24:. This valve lifteris pivoted to the lever 21 at a point 25 so that when the pressure inthe chamber 17 exceeds "that in the'chambe'r l6 'plus'the Weight of thewater onthediaphragm, the valve 20 will'open; The valve lifter24t isprovided with apassage 26- ex tending up through from the chamber '17 tothe chamber 16. At the upper end this passage is substantially closed bya filter 27...

valve lifter 24 which is shaped to receive it.

It is shown as provided with' two filters and V asmall plate 28 having acenter .bleed passage of very fine dimensions. 'Tl1e'se fil s5 ters, orat least the one on the outside, are

wh'ich might'be deposited in the very small passage and plug it up. Itis shown'jwith two filters so as to be reversible; Heretofore material40 which is porous and will'expand,

when wet. This may be in one piece or several, if desired, but it isdesirable to fill loo 7 the entire interior of this head clear down tothe screen of the filter 27.

I have shown the invention as used with substantially the same means forretaining the quick closing of the exhaust valve and eliminating thehammering action due to any vibration thereof as shown in the abovementioned Rockwood patent. Forthis'puras provided with a mushroom plate31 having a plate 32 secured to the sameand both having chamberstherein. One of these chambers is connected by a pipe '33'to the drainchamber of the dry-pipe valve. A. diaphragm 34 extends across the spacebetween these two chambers. It carries a stem 35 which is provided witha relief valve 36. This cooperates with the plate 31 which'has a surfaceforming a valve seat. A. spring 85 37 is arranged to keep the valve 36closed. This operates in substantially themanner shown in the abovementioned patent, although its details are different.

When water has been admitted to a drycelerator provided with the bleederprotector herein described the sponge is immediately swollen with waterandgently presses against the interior surfaces of the casing 29.Therefore, any deposition of silt or dirt would simply tend to fill theholes with a wet mass. On withdrawing the water and admitting the airunder pressure, no deformation of the sponge would occur unless 100 allof the small holes, those on the bottom of the circumference as well asthose more exposed to gravity, are plugged. If such should be the case,however, then the air would slightly compress the spongeat one or moreholes andpenetrate it, through the greater surface thus exposed, to thefilter and bleed hole. Thus the use of spongy material automaticallysupplies just the right increase of surface to the entering air 'toprevent its material exclusion, without exposing that surface to theaction of float ing silt.

The effect of such an arrangement is to greatly prolong the useful-lifeof the sponge, 115 for the casing, surrounding as it does, the spongyparticles, protects them from continual infiltration of the circulatingdirt and the dirt itself seals only those sponge surfaces directlyopposite and protruding into 120 the holes. The gentle elasticity of thewet sponge precludes any material loss .of air pressure when air isbeing forced through it. When once wet the sponge would remain wetthroughout its life, as the relative humidity of the atmosphere in adry-pipe system is 100%, owing to the presence of .the .priming water inboth the exhauster and the dry-pipe valve.

cleaning or reversal of the screens in the pose the bottom of the casingis shown pipe system containing an exhauster or ac The casing 29 can beremoved readily for filter 27 and for the replacement of the spongematerial if that should prove to be desirable. This element will havegreat durability on account of the material. used and need be replacedonly very seldom. When used for a long period of time without operationof the device due to the opening of any sprinkler heads it will stillretain its relative properties without inspection-of anykind.

Although I haveill-ustratedand described the invention as used inconnection withconstructions similar to those shown in the abovementioned patents, that is simply for convenience, and I donot wish tobe limited to these particular constructions or particular systems towhich they relate. Furthermore, changes int-he construction of theinvention itself can be made by any person skilled .in the art withoutdeparting from the scope of the invention as expressed in the claims.

Therefore, I do not wish to be limited in these respects but what I doclaim is 1. The combination of a member having a passage through it forair and provided with an externally threaded head, of a filter locatedon the outside of the head for protecting a fine bleed passage, and aperforated'casing screwed onto the head to hold the filter in place andfilled with porous compressible material to protect the bleed passagefrom impurities of air and water.

2. The combination of a member having a passage through it for air andprovided with a head, of a filter screen located on the head, a platespaced from thescreen and having a fine bleed passage, and a perforatedcasing on the head filled up to said screen with sponge to protect thebleed passage from lmpurities.

In testimony whereof I have' hereunto aflixed my signature.

' HJALMAR G. CARLSON.

